1. Field of the Invention
The present invention relates to a printer.
2. Description of the Prior Art
FIG. 1 is an exploded perspective view of a conventional heat transfer color printer. As shown in the drawing, the conventional heat transfer color printer comprises the following components or portions: a lower cabinet 1; a circuit portion 2; a power supply panel 3; a pinch roller 4; a capstan roller 5, against which the pinch roller 4 is adapted to abut to impart a driving force to the same; a platen roller 6, which, together with the pinch roller 4 and the capstan roller 5, constitutes a paper feeding mechanism; a main motor 7 for driving the pinch roller 4 and the platen roller 6; a pinch lever 8 adapted to be interlinked with the movement of a cam to cause the pinch roller 4 to be brought into contact with the capstan roller 5 or to cancel the contact thereof; a release roller 9 for releasing an ink film from paper; a paper feed roller 10 for bringing the paper into contact with the platen roller 6; a paper guide 11 for guiding the paper; and a paper support 12 for supporting the paper wound into the form of a roll. The printer further comprises a cover frame 13; a lock lever 14; a lock lever shaft 15, which engages or disengages with the lock lever 14 to open or close the cover frame 13; a ribbon feed gear 16 disposed on the cover frame 13 and adapted to effect positioning of one end of a ribbon feed in which an ink film is rolled; a ribbon holder 17 similarly disposed on the cover frame 13 and adapted to impart a pressing force against the other end of the ribbon feed; a head holder 18; a head 19 secured to the head holder 18; a head arm 20 which is interlinked with the operation of a cam and to which the head 19 is secured; a cooling fan 21 for radiating heat from the main motor 7, the circuit portion 2, and the like; an operation panel 22; a top cover 23; and an upper cabinet 24.
In the conventional heat transfer color printer, the paper feeding and printing are carried out in the manner illustrated in FIGS. 2a and 2b.
First, during paper feeding, as illustrated in FIG. 2a, by virtue of the counterclockwise rotational driving forces of the pinch roller 4 and the platen roller 6, the paper is fed from the paper holder 26 by an amount corresponding to one image plane in the direction of the arrow A. At this time, the head 19 is located away from the platen roller 6, the ink film 27 is in a stopped state, and printing is not effected.
Incidentally, in FIG. 2a, reference numeral 28 denotes an ink film holder, while numeral 29 denotes an ink film takeup holder.
During printing, as shown in FIG. 2b, the platen roller 6 and the pinch roller 4 rotate clockwise, and the paper 25 is thus unwound by the amount of one image plane in the direction of the arrow B. At this time, the head 19 is in contact with the platen roller 6, and the ink film holder 28 and the ink film takeup holder 29 rotate counterclockwise, so that the ink film 27 and the paper 25 are unwound in the direction of the arrow B in an interlinking relationship. Thus, heat is applied from the head 19 to the ink film 27, and predetermined printing is effected on the paper 25.
Incidentally, yellow, magenta, and cyan are arranged on the ink film sequentially for each image plane, and color printing is effected by repeating the above-described operation three times.
The printing section is arranged as described above. The paper for which printing has been completed is discharged to the outside by a paper discharging device. FIG. 3 is a partial perspective view of a conventional paper discharging device. In the drawing, upper and lower rollers 30, 31 are rotatively driven by a drive motor 32. Reference numerals 30a, 31a denote upper and lower shafts, respectively. Numerals 33, 34 are upper and lower chutes, respectively, and the paper is guided therebetween to be discharged.
With such an arrangement, however, it is necessary to machine the upper and lower shafts 30a, 31a with high precision, and a large number of components, including the drive motor 32, is required, thereby hampering a reduction in the costs.
In addition, in the case of a heat transfer color printer, in terms of its basic principle, it is necessary to reciprocate the paper a plurality of times, as described above. Accordingly, during printing, it is necessary to open the gap between the upper and lower shafts 30a, 31b and to prevent the advance of the paper 25 from being hindered by the upper and lower rollers 30, 31. At the time of discharging the paper, it is necessary to discharge the paper by bringing the upper and lower rollers 30, 31 into contact with each other. For this reason, there has been a drawback in that the paper discharging device is complicated.